Modem hearing aids, or hearing aid devices, typically include digital electronics to enhance the wearer's listening experience. Hearing aids with airborne delivery of a signal that the user experiences as sound typically use transducer and electro-mechanical components, which are connected via wires to the hearing aid circuitry. In addition to transducers, hearing aids incorporate A/D converters, DAC's, signal processors, memory for processing the audio signals, and wireless communication systems. The components frequently include multiple housings or shells that are connected to assemble the hearing aid. A coating may be applied to the housing or parts of the housing, e.g. at crevices, to reduce the risk of moisture ingress, or other fluid substances, such as cerumen etc.
In hearing aids having a speaker unit, i.e. a transducer, positioned in the ear canal of the user, a so-called receiver-in-the-ear, or receiver in-the-canal, hearing aid a connecting element mechanically connecting a behind-the-ear element to an in-the-ear element may surprisingly additionally be the host of a range of elements, including an antenna element or combinations of multiple elements.
The antenna element may be part of a larger antenna structure or be the sole part of the antenna structure. When communicating wirelessly at radio frequencies, e.g. 2.4 GHz, 5 GHz or at least in the range generally from around 1 GHZ to around 10 GHz, to and/or from the hearing aid positioned at the ear, the head of the person wearing the hearing aid will attenuate the signal. Using the connecting element to host, at least part of, the antenna is advantageous. Using an antenna embedded in a part completely positioned behind the pinna may degrade the signal in certain directions, e.g. to/from the opposite side of the head.
Further, when including electrical components in the in-the-ear part, there is an increased need for, wired, communication bandwidth between the two parts, e.g. in the form of multiple wires.
The present disclosure provides a solution that addresses at least some of the above-mentioned problems. The present disclosure provides at least an alternative to the prior art.
The present disclosure provides, in a first aspect, an assembly for used with a hearing aid, wherein the assembly comprises a connector for mechanically interconnecting an in-the-ear part with a behind-the-ear part. Herein the term connector is used for both the part interconnecting an in-the-ear part with a behind-the-ear part, but also for the part of the connector that connects to the behind-the-ear part.
An object of the present disclosure is achieved by a hearing device comprising a first portion adapted for being arranged behind an ear of a user for providing a signal, an output transducer for converting the signal to an acoustic output, a coupling element coupling to the first portion, an antenna comprising an external antenna arranged at least externally to the first portion and an internal parasitic element, a feeding unit configured to supply a current to the external antenna, and the feeding unit is further configured to supply the current to the internal parasitic element via a wireless coupling, a wireless interface for receiving and/or transmitting data by means of the antenna, and wherein the coupling element comprises the external antenna, and wherein the coupling element comprises an electrically conducting element coupled to the wireless interface, and wherein the electrically conducting element is at least a part of the external antenna.
Further, in the housing of the first portion or first part, i.e. the behind-the-ear part, a parasitic element may be present. Thus, the hearing device may comprise an antenna comprising an external antenna arranged at least externally to the first portion and an internal parasitic element arranged internally in the first portion, a feeding unit configured to supply a current to the external antenna. The advantage of combining the external antenna and the parasitic element is, at least, that the bandwidth of the antenna increases and that the obtained improvement of the bandwidth is obtained by not increasing the size of the hearing device. The parasitic element is then tuned to the operation frequency, or frequency band, of the hearing device.
The parasitic element, e.g. the internal parasitic element, may be part of the printed circuit board connected to a ground plane such that the parasitic element only receives a current via the magnetic coupling or via the capacitive coupling. The current from the feeding unit may be transferred via the ground plane and/or via the external antenna and wireless coupled to the parasitic element.
The parasitic element may be a passive element being electrically conductive and connected to the ground plane. An electrical length of the internal parasitic element may be λ/4 or λ/4+x*λ/2, where x is a number, such as 0, 1, 2, 3 etc. The electrical length of the internal parasitic element may be adapted to the ground plane and/or the external antenna. The electrical length may be any length, and where the impedance match between the internal parasitic element and the external antenna is obtained by an impedance matching circuit. The impedance matching circuit may comprise one or more capacitance and/or one or more coils. The impedance matching circuit may be connected to the internal parasitic element and ground plane or between the external antenna and the ground plane.
The connector, or plug, connecting the connector to the behind-the-ear part may be a flex tab connector, e.g. a male flex tab. The plug may have a plug housing. Alternatively to the flex tab connector, the connector may comprise a plurality of pins extending parallel to each other in a direction perpendicular to a surface of the connector. For ensuring interoperability an adaptor may be provided, wherein the adaptor comprises a socket for connecting to the flex tab, and a plurality of pins corresponding to the desired number of connections in the behind-the-ear part. This will allow the connector with the flex tab to engage with other types of sockets. Between the flex connector and the pins of the adaptor suitable interconnections are provided. Preferably, 5 pins are provided, but the number may be different, such as higher than five. The adaptor may include a protrusion, or groove, to ensure that the adaptor does not rotate after being mounted in the behind-the-ear part and/or connector, further, apart from reducing or preventing rotation the protrusion and/or groove may provide stress relief of rotational forces exerted on the pins. The adaptor may include a bend in the sense that the socket for the flex tab and the pins may form an angle, i.e. not extend parallel in substantially the same plane.
The receiver and the flexible substrate may connect so that a bended part of the flexible substrate connects to a surface part of the receiver. This may e.g. be an end surface of the receiver that connects to a bended end of the flexible substrate, which may for instance be bended around 90 degrees relative to the nearest part of the flexible substrate. In the alternative, or combined herewith, the receiver may comprise a part that extends so that a substantially flat surface part may be used to connect to the flexible substrate so that the flexible substrate part connecting to the receiver and surface part of the extending part of the receiver to connect to are substantially parallel.
The flexible substrate may extend into the plug housing where a number of vias connect pins to electrically conductors on or in the flexible substrate. This allow the flexible substrate to be used in embodiments where the connector comprises pins for connecting with e.g. an behind-the ear part. To omit the vias, the pins may be soldered directly to the flexible substrate. The vias may be litz wires.
The connector is configured to establish electrical connection between the in-the-ear part and the behind-the-ear part. The electrical connection is established via two or more conductors formed at a flexible carrier having a protective cover or tubing. An output transducer may be included in the in-the-ear part or in the behind-the-ear part. The flex tab connector is electrically connected to the receiver and configured to mate with the receptacle connector to provide electrical connection between the receiver and the circuitry, and includes a flex substrate and conductive contacts constructed on the flex substrate. Flex tab connector is a bendable flex connector, could also be named a flexible connector, flex circuit connector, or flexible circuit connector, and may include conductive contacts constructed on a flex substrate, could also be termed as a flexible substrate, flex circuit substrate, or flexible circuit substrate. Conductive contacts, e.g. flex pads which may be made of mechanically flexible conductive traces such as copper traces, the connector is thus substantially bendable.
The present disclosure provides, in a second aspect, a hearing aid. The hearing aid may be of a kind comprising a first part configured to be positioned at or behind the ear of a user and a second part configured to be positioned at or at least partly in the ear canal of the user. These first and second parts may each comprise an appropriate housing. The first housing may be generally oblong and shaped so as to fit in the area between the pinna and the head of the user, in which position the first housing is less visible. The second housing may be shaped so as to provide a tight fit in the ear canal, alternatively, a further device may be provided to establish contact to an inner wall of the ear canal, e.g. such a device is sometimes referred to as a dome. The hearing aid may further comprise a third part connecting the first part and the second part. This third part provides mechanical connected between the first and the second part. The second part may comprise an output transducer configured to provide an acoustic signal to be provide to the user's ear canal. This could be a so-called receiver transforming an electrical signal to an acoustic signal. The electrical signal is most often provided from electronics in the first, i.e. the behind the ear, part. The first part may comprise one or more, e.g. two, input transducers, such as microphones. The second part, i.e. the in the ear part, may additionally comprise one or more input transducers, e.g. one facing towards the surroundings and alternatively or additionally one facing towards the area between the second housing and the tympanic membrane. The input transducer facing towards the surroundings could be used for detecting sounds to be processed so as to, at least partly, compensate for the users hearing loss. The hearing loss may be age dependent and/or noise induced. The compensation could be achieved by hearing assistance electronics, e.g. including a filter and an amplifier. The input transducer facing towards the tympanic membrane could be used for detecting various event such as own voice activity and/or for detecting/countering occlusion effects. The third part may comprise a transmission path configured to provide electrical connection between the first part and the second part. The transmission path may include several sub-paths, and may be separate from other electrical connections between the first and second parts. The transmission path may be a transmission line or even a multitude of transmission lines. The transmission path may be configured to conduct a signal from the first part to the second part, and/or vice versa. The first part may comprise various electronic components such as one or more signal processors for processing signals from the one or more input transducers, a power source, which may be rechargeable, communication devices such as transmission and reception devices, or any other kinds of electronic components needed in a hearing aid. Further, one or more filter banks for converting time domain audio signals into frequency domain may be included, as well as filter banks for reconverting back to time domain. Further, one or more electronic components may be included in the second housing, e.g. a signal processor for processing e.g. signals from an input transducer in the second housing, one or more memory devices, one or more processors for other purposes than signal processing or any other suitable electronic components. The transmission path may, at least partially, be established via a flexible substrate having a plurality of electrically conductive paths. The flexible substrate may have a length and a width. The width of the flexible substrate may be a diameter. Such a flexible substrate may be an oblong substrate that does not stretch much. Preferably, the flexible substrate is at least flexible in a direction perpendicular and/or to the top surface. If the flexible substrate has a generally rectangular cross-section, the flexibility may be present in the direction perpendicular to the long side of the rectangular cross-section as well as the direction perpendicular to the short side of the rectangular cross-section, while the substrate is not notably flexible along the length of the flexible substrate. The third part may further comprise a protective member mounted along the length of the flexible substrate. Advantageously the protective member surrounds the flexible substrate along the length, thereby protecting the flexible substrate from the environment. The protective member may further comprise strengthening fibers increasing the pull strength of the third part. The fibers may for instance be Aramide fibers. The fibers is contemplated in increase the tensile strength. When the hearing aid is to be mounted on or at the ear, the user may grab the hearing aid at the third part enabling him or her to position the second part in the ear canal opening or further into the ear canal depending on the shape and form of the second part. Further, when dismounting the hearing aid the user may pull the third part so as to remove the second part from the opening of the ear canal.
Using a flexible substrate as a carrier for electrical connection and/or communication between a behind-the-ear part and an in-the-ear part is advantageous in at least that a well-defined arrangement of the electrical connections is achieved, whereas when using twisted litze wires the exact relation between the wires is unknown, with possible undefined cross talk between the signals in the wires, whereas conductors embedded inside or at or on the surface of the flexible substrate is controllable and well-defined. Further, the impedance using the flexible substrate will be more well defined as well compared to the twisted litze wires.
The third part may be formed so that the protective cover includes a passageway conducting an airborne acoustic signal from an output unit in the first housing to the in-the-ear part, which has an output opening so as to output the airborne acoustic signal to the users ear canal. In such an arrangement the flexible substrate may be used, e.g., exclusively for an antenna function, or for establishing electrical connection to components in the in-the-ear part, e.g. input transducer or input transducers, processing unit or units, memory unit or units, or combinations or other types of units. Still further, an output transducer having both an in-the-ear speaker and a behind-the-ear speaker may be established.
The flexible substrate may have an overall, generally rectangular cross section. The cross-section of the flexible substrate may have another geometry and may optionally include minor other geometries, this could at least be in areas where optional electrical components are arranged at the surface of the flexible substrate. This could also include the area at the transmission path, where a conductor may be lowered, or embedded, relative to the surface of the flexible substrate.
Optionally, conductive path or paths may be formed at the short side of a flexible substrate having a rectangular shaped cross-section.
The hearing aid in general may include a variety, and possibly a plurality, of specialized electrical components. Such component or components could be one or more of gyrometer, thermometer, heart rate monitor, capacitor, inductor, resistor, integrated circuit e.g. asic, microphone, gyroscope, accelerometer, inclination sensor, compass, light sensor or any combinations thereof. The mentioned components may as an alternative or addition optionally be arranged in the housing of the first and/or second part.
The flexible substrate may be a multi-layer flexible circuit board where at least part of the plurality of transmission paths could be formed on respective opposite sides of the flexible substrate. This could e.g. be two long sides of a flexible substrates having a rectangular cross section. Alternatively, or in addition, one or more conductors could be formed in intermediate layers. Further, one or more electrical components may be embedded within the multi-layer flexible circuit board.
The hearing aid may further comprise a wireless interface and an antenna. This could e.g. enable wireless communication to other devices, advantageously using a protocol such as Bluetooth or Bluetooth Low Energy or other suitable protocol. Further advantageously, at least part of the antenna may be formed along the flexible substrate. This could allow the antenna to be at least partly exposed, i.e. not substantially covered by a part of the pinna or ear canal. Placing the antenna inside the ear canal is at some frequencies detrimental to the signal as the head will attenuate the signal substantially, at least in the direction through the head. Bringing the antenna as close to free space as possible lower losses in tissue of the head of the user, especially around e.g. 2.4 GHz. The antenna may include a part not being part of the third part. e.g. a part of the antenna may be formed inside the first part, this could e.g. be a wire or the like arranged inside the housing of the first part acting together with the part in the third part to form the antenna.
It could be advantageous to form at least part of the antenna using one, or more, of the electrically conductive paths on one surface of the flexible substrate. This allows predictable antenna properties and lowers variation from production. Alternatively, or in addition, a wire may be positioned along at least part of the length of the flexible substrate to be used as part of the antenna. The wire may e.g. be arranged in a spiral-like or helical-like geometry around at least part of the flexible substrate.
The antenna may extend at least part of the length of the flexible substrate. If the antenna is at least partly formed by a conductor in the flexible substrate a component may be position to terminate the antenna thereby providing a well-defined length of the antenna. The antenna may include an antenna trap. The trap could divide at least part of the length of the part of the flexible substrate where the antenna is formed so that the antenna is configured to operate at at least two different wavelengths, and thereby provide, in effect, two different modes of operation for the antenna. This could e.g. be used for communication where at one frequency data is received and where at another frequency data is sent. Further, the two modes could simply provide transmission and reception at two different wavelengths so that a transceiver or radio in the hearing aid could be operated at either frequency at any given time. This could for instance provide a carrier frequency of around 2.4 GHz and/or around 5.1 GHz. Other carrier frequencies could be supported. The well-defined length of the antenna, when looking e.g. at a set of connectors of different length, is particular useful in that the overall length of the connector may be different for different people as the size of ears and subsequently the needed distance between ear canal and behind-the-ear area. It could be so that the length of the antenna is shorter than the shortest length of a connector in a set of connectors each having different lengths. This would provide a uniform antenna performance for antennas in such a set of connectors. If the antenna length is tied to the length of the connector, the antenna performance will not be the same for a range of hearing aids. The conductor may also be terminated in other ways. An electrical component could be positioned at a position between the respective ends of the flexible substrate so as to isolate the antenna. i.e. so that the length of the antenna is only a part of the length of the flexible substrate. The wireless interface, e.g. a radio, may include a function for setting the wireless interface in a low power or off mode, e.g. a flight mode, so that the wireless interface does not emit power, or at least reduce the emission to a low level. The wireless interface may thus decode the signal received via an antenna, the decoding could include translating the received antenna signal to a digital signal and/or transforming it. This could be done to extend battery lifetime and/or comply with regulations of electromagnetic emission in specific areas e.g. in airplanes or hospitals.
The second part may include a first input transducer, and the hearing aid may further comprise a processor, either in the first part or in the second part, configured to process the output from the first input transducer so as to compensate for a hearing loss of the user. This processor could be composed of several processors each performing tasks. Appropriate memory units could also be included. The processing could include filtering, amplification, frequency transpositioning, feedback management, addition of e.g. tinnitus treatment signal, or other suitable processing.
The first part may further comprise a second input transducer, and the processor may then further be configured to establish a processed audio signal based on output from both the first input transducer and the second input transducer. This could e.g. enhance directionality of a system based on the two input transducers. Other functions such as own voice detection or occlusion detection may be performed using such as arrangement, however, an alternative number of input transducers may be used for these functions as well.
The first part may include a third input transducer, and the hearing aid may then comprise a processor, either in the first part and/or in the second part, configured to process the output from the input transducers so as to compensate for a hearing loss of the user. The processed output from the input transducer or input transducers may then be outputted to the user via the output transducer. This third input transducer may be the only input transducer of the hearing aid. Either of the first, second and/or third input transducers may comprise more elements, e.g. one omnidirectional microphone or two omnidirectional microphones or more omnidirectional microphones. Output from such at least two omnidirectional microphones may be combined for forming a directional microphone system, as outlined elsewhere in the present specification.
The input transducers mentioned here may be individual microphones or microphone systems each comprising two or more individual microphones. Further, two or more input transducers may be functionally combined to achieve the required functionality of the audio processing.
According to another aspect of the present disclosure a method of producing a connection member for a hearing aid is provided. The hearing aid may comprise a first part configured to be positioned at or behind the ear of a user and a second part configured to be positioned at or at least partly in the ear canal of the user.
The method according to the other aspect may comprise providing a flexible substrate having a plurality of electrically conductive paths. The flexible substrate may for instance be relatively thin bendable material such as the so-called flex PCB The flexible substrate may have a first length along the longest side. The method may comprise providing a protective member having an elongated shape and an internal cavity. The protective cover may be added to protect, among others, the flexible substrate from the rather hostile environment at the ear of a hearing aid. The protective member may have an initial length being smaller than the first length. This may be advantageous in processes where the protective member is subsequently stretched and thereby reduced in diameter. The method may comprise arranging the protective member and the flexible substrate so that the flexible substrate is located in the cavity of the protective member. The method may comprise stretching the protective member so as to elongate the protective member along the longest side of the flexible substrate thereby narrowing the cavity. By stretching the protective cover the diameter will reduce and may thereby conform to the size and shape of the flexible substrate. The stretching may be accomplished with the aid of clamps and or other holding or retention devices for ensuring that the protective cover does not slip while being stretched.
The method may comprise that the protective member is heated during and/or before stretching. This could help the stretching process by making the protective cover more soft and more easily deformable during the pulling process.
The method may further comprise providing a coating to the flexible substrate before mounting the protective member. The coating may provide enhanced protection to the flexible member from ingression of substances, such as sweat, cerumen and the like.
All or nay aspects and/or features mentioned herein may be combined, either individually or in combination with one or more of the other aspects and/or features.